Electronic optical devices, such as cameras, displays, and scanners, generally require an integrated circuit optoelectronic device which includes an integrated circuit which is responsive to optical images. The integrated circuit can include light sensitive devices, such as CCDs or active pixel sensors. The placement of the integrated circuit in the optoelectronic device requires precise alignment between the light sensitive devices of the integrated circuit and a light receiving opening or lens of the optoelectronic device.
FIG. 1 shows an integrated circuit optoelectronic device according to the prior art. Light sensitive devices 2 are formed on a first substrate 4. The light sensitive devices 2 receive light and generate electrical signals proportional to the intensity of the received light. The first substrate 4 is electrically interconnected to a second substrate 6. The second substrate 6 is electrically interconnected to a third substrate 8 (typically a printed circuit board).
The first substrate 4 and the second substrate 6 are electrically interconnected through bonding wires 10. The second substrate 6 and the third substrate 8 are typically electrically interconnected through rigid conductive leads 12. The placement of the light sensitive devices 2 with respect the rigid conductive leads 12 is difficult to control. Therefore, the placement of the light sensitive devices with respect to the third substrate is difficult to control.
The optoelectronic device further includes a lens 14. The lens 14 receives and concentrates light onto the light sensitive devices 2. Clearly, the alignment of the lens 14 with respect to the light sensitive devices 2 effects the operation of the optoelectronic device. Typically, the lens 14 is adjustably referenced with respect to the third substrate 8. That is, the lens 14 can be adjusted in position with respect to the third substrate 8, but when not being adjusted, the position of the lens 14 is fixed.
The optoelectronic device includes a transparent area 16 which allows light passing through the lens 14 to be received by the light sensitive devices 2.
To align the lens 14 with the light sensitive devices 2, the lens 14 is adjusted in position until a maximal response is generated by the light sensitive devices 2. This can be accomplished, for example, by generating a video image from the response of the light sensitive devices 2 and displaying the response on a video monitor. The position of the lens 14 is adjusted until the response displayed by the video monitor is optimal. This approach can be very expensive in a manufacturing environment. The process is time consuming and requires the lens adjustment process.
FIG. 2 shows another integrated circuit optoelectronic device according to the prior art. This device includes an edge surface 20 formed on the second substrate 6. The edge surface 20 provides a reference point between the light sensitive devices 2 and the second substrate 6. The second substrate 6 is interconnected to the third substrate 8 through the rigid conductive leads 12. Therefore, the light sensitive devices 2 are physically referenced to the third substrate 8. The lens 14 is fixed in position with respect to the third substrate 8. Therefore, the light sensitive devices 2 are referenced with respect to the lens 14.
To control the placement of the light sensitive devices 2 with respect to the edge surface 20 requires precise machining and cutting of the edges of the second substrate 4. The machining and precise cutting of the edges is expensive and requires extra processing steps.
Both of the described approaches add extra manufacturing processing steps. Consequently, both approaches are very expensive.
It is desirable to have an optoelectronic device package in which the light sensitive devices of an integrated circuit within the optoelectronic device package is inexpensively aligned with an opening or lens associated with the optoelectronic device package. It is desirable to eliminate the expensive processing steps previously described.